Rocker arm assembly

Abstract

A combined exhaust and engine brake rocker arm assembly configured to selectively open first and second exhaust valves, includes a rocker arm body, an exhaust rocker arm assembly formed in the rocker arm body, and an engine brake rocker arm assembly formed in the rocker arm body and configured to operate in a collapse mode and a rigid mode. The exhaust rocker arm assembly is configured to selectively engage a valve bridge to open the first and second exhaust valves, and the engine brake rocker arm assembly is configured to selectively engage the valve bridge to open only the first exhaust valve.

What is claimed is: 
     
       1. A valve train assembly associated with first and second exhaust valves, the assembly comprising:
 a valve bridge including a main body and a lever rotatably coupled to the main body, the main body configured to engage the first and second exhaust valves, and the lever configured to engage the first exhaust valve; and 
 a combined exhaust and engine brake rocker arm assembly comprising:
 a rocker arm body; 
 an exhaust rocker arm assembly formed in the rocker arm body; and 
 an engine brake rocker arm assembly formed in the rocker arm body and configured to operate in a collapse mode and a rigid mode, 
 wherein the exhaust rocker arm assembly is configured to selectively engage the valve bridge main body to open the first and second exhaust valves, 
 wherein the engine brake rocker arm assembly is configured to selectively engage the valve bridge lever to open only the first exhaust valve, 
 wherein the lever is coupled to the main body such that rotation of the lever and engagement of the first exhaust valve occurs without rotation of the main body, 
 wherein the main body includes an first aperture, the lever at least partially disposed within the first aperture, 
 wherein the lever is rotatably coupled to the main body by a bridge pin extending through the main body, 
 
 wherein the main body further includes a second aperture and a third aperture to each receive the bridge pin therethrough, 
 wherein the lever includes first opposed openings each receiving the bridge pin therethrough, and 
 wherein the lever includes second opposed openings. 
 
     
     
       2. The valve train assembly of  claim 1 , wherein the exhaust rocker arm assembly comprises an exhaust capsule assembly disposed in a bore formed in the rocker arm body,
 wherein the exhaust capsule assembly comprises a plunger assembly and a stopper, the plunger assembly including a first plunger body and a second plunger body, wherein a chamber is defined between the first and second plunger bodies configured to receive a supply of fluid. 
 
     
     
       3. The valve train assembly of  claim 2 , wherein the stopper includes an annular bore formed therein, and a lost motion biasing mechanism is at least partially disposed in the annular bore, the lost motion biasing mechanism configured to bias the stopper and the plunger assembly away from an upper wall of the bore. 
     
     
       4. The valve train assembly of  claim 3 , wherein the stopper includes an annular groove formed therein, the annular groove configured to selectively align with a fluid port fluidly coupled to the engine brake rocker arm assembly. 
     
     
       5. The valve train assembly of  claim 1 , wherein the engine brake rocker arm assembly comprises a brake capsule assembly disposed in a bore formed in the rocker arm,
 wherein the bore comprises a first bore and a second bore formed in the rocker arm, the brake capsule assembly comprising a brake plunger assembly disposed in the first bore, and an actuator assembly disposed in the second bore. 
 
     
     
       6. The valve train assembly of  claim 5 , wherein the brake plunger assembly includes a check ball assembly and a first plunger body movable relative to a second plunger body, the first and second plunger bodies defining a chamber therebetween configured to receive a supply of fluid, the check ball assembly disposed in the chamber between the first and second plunger bodies. 
     
     
       7. The valve train assembly of  claim 1 , further comprising a valve shoe rotatably coupled to the lever, the valve shoe configured to engage the first exhaust valve, wherein the valve shoe is rotatably coupled to the lever by a valve shoe pin extending through the lever. 
     
     
       8. The valve train assembly of  claim 1 , wherein the first aperture defines an inner perimeter, and the lever defines an outer perimeter that fits within the inner perimeter. 
     
     
       9. The valve train assembly of  claim 1 , wherein the lever is disposed within the valve bridge main body. 
     
     
       10. The valve train assembly of  claim 1 , wherein the lever is rotatably coupled to an inner wall of the valve bridge main body, the inner wall defining the first aperture. 
     
     
       11. The valve train assembly of  claim 1 , further comprising a valve shoe pin extending through the second opposed openings and a valve shoe to rotatably couple the valve shoe to the lever. 
     
     
       12. The valve train assembly of  claim 1 , further comprising a stop flange extending outward from the lever, the stop flange configured to selectively engage a bar of the valve bridge main body to limit downward movement of the lever. 
     
     
       13. The valve train assembly of  claim 1 , wherein the engine brake rocker arm assembly includes a brake plunger assembly having a socket, wherein the socket is coupled to the lever to maintain constant contact therewith for dynamic stability. 
     
     
       14. The valve train assembly of  claim 1 , wherein the first aperture is formed through an upper surface of the main body, and the lever is rotatably coupled to side surfaces of the main body. 
     
     
       15. The valve train assembly of  claim 14 , wherein the exhaust rocker arm assembly selectively engages the upper surface to open the first and second exhaust valves. 
     
     
       16. The valve train assembly of  claim 1 , wherein the first aperture is defined by a first pair of opposed internal walls of the main body, and a second pair of opposed internal walls of the main body. 
     
     
       17. A valve train assembly associated with first and second exhaust valves, the assembly comprising:
 a valve bridge including a main body and a lever rotatably coupled to the main body, the main body configured to engage the first and second exhaust valves, and the lever configured to engage the first exhaust valve; and 
 a combined exhaust and engine brake rocker arm assembly comprising:
 a rocker arm body; 
 an exhaust rocker arm assembly formed in the rocker arm body; and 
 an engine brake rocker arm assembly formed in the rocker arm body and configured to operate in a collapse mode and a rigid mode, 
 wherein the exhaust rocker arm assembly is configured to selectively engage the valve bridge main body to open the first and second exhaust valves, 
 wherein the engine brake rocker arm assembly is configured to selectively engage the valve bridge lever to open only the first exhaust valve, 
 wherein the lever is coupled to the main body such that rotation of the lever and engagement of the first exhaust valve occurs without rotation of the main body, 
 wherein the main body includes an aperture, the lever at least partially disposed within the aperture, 
 wherein the lever is rotatably coupled to the main body by a bridge pin extending through the main body, 
 
 wherein the engine brake rocker arm assembly comprises a brake capsule assembly disposed in a bore formed in the rocker arm, 
 wherein the bore comprises a first bore and a second bore formed in the rocker arm, the brake capsule assembly comprising a brake plunger assembly disposed in the first bore, and an actuator assembly disposed in the second bore, 
 wherein the brake plunger assembly includes a check ball assembly and a first plunger body movable relative to a second plunger body, the first and second plunger bodies defining a chamber therebetween configured to receive a supply of fluid, the check ball assembly disposed in the chamber between the first and second plunger bodies, 
 wherein the actuator assembly comprises a pin disposed in a retainer, the pin operably associated with the check ball assembly, wherein the second bore is configured to receive a supply of fluid such that the retainer is translated upwardly within the bore to draw the pin away from contact with the check ball assembly and wherein the first plunger body is received by a socket coupled to the valve bridge lever.